Abstract: Four sections of dolomite, grainstone, micritic limestone and granulir micritic limestone in Dawangou of Keping area are selected, and their structural fractures are statistically analyzed. The results of fracture density measurements show that the value of the fracture density from big to small is dolomite, grainstone, micritic limestone and granulir micritic limestone, which means in the same tectonic setting dolomite is easier to produce structural fracture. Also, the purer and the bigger granules the carbonate have, for example limestone, the more difficulty to produce structural fracture. The relationship between the structural fracture and the rock mechanics parameters is discussed.

Key words: lithology, structural fracture, carbonate rock, fracture density

摘要： 针对柯坪大湾沟地区白云岩、颗粒灰岩、泥晶灰岩和颗粒泥晶灰岩4种碳酸盐岩, 选取4个剖面, 对其构造裂缝发育情况进行统计分析。结果表明, 裂缝面密度强度由大到小依次为白云岩、颗粒灰岩、泥晶灰岩和颗粒泥晶灰岩, 即在相同构造环境下, 白云岩最容易产生构造裂缝。同时发现质纯粒粗的碳酸盐岩(如颗粒灰岩)相对脆性大, 比泥质细粒的碳酸盐岩(如颗粒泥晶灰岩)更易发育构造裂缝。最后对碳酸盐岩裂缝面密度与岩石力学参数之间的关系进行了探讨。

关键词: 岩性, 构造裂缝, 碳酸盐岩, 裂缝面密度